This New Record in Laser Beam Stability Could Help Answer Physics’ Biggest Questions

Scientists are aiming to create a global network of atomic clocks that will allow us to better understand the fundamental laws of physics, investigate dark matter, and navigate across Earth and space more precisely.

The clocks will have to be reliably and speedily linked together through layers of the atmosphere. New research outlines a successful experiment with a laser beam that has been kept stable across 2.4 kilometers (1.5 miles).

For comparison, the new link is around 100 times more stable than anything that’s been put together before.

“The result shows that the phase and amplitude stabilization technologies presented in this paper can provide the basis for ultra-precise timescale comparison of optical atomic clocks through the turbulent atmosphere,” write the researchers in their published paper.

The system adds to the research that came last year in which scientists developed a laser link capable of holding its own through the atmosphere with unprecedented stability.

In the new study, researchers shot a laser beam from a fifth-floor window to a reflector 1.2 kilometers (0.74 miles) away. The beam was then bounced back to the source to achieve the total distance for a period of five minutes.

They used noise reduction techniques, temperature controls, and made tiny adjustments to the reflector to keep the laser stable through the air.

That setup involved a pulse laser instead of the continuous wave laser tested in this new study.

915 questions with answers in LASER | Science topic

“Both systems beat the current best atomic clock, so we’re splitting hairs here, but our ultimate precision is better,” says astrophysicist David Gozzard from the University of Western Australia.

If Einstein’s ideas are correct, the clock further away from Earth’s gravity should tick ever-so-slightly faster.

Lasers like this could also be used for managing the launching of objects into orbit, for communications between Earth and space, or for connecting two points in space.

“Of course, you can’t run fiber optic cable to a satellite,” says Gozzard.

The research has been published in Physical Review Letters.

Leave a Reply

Your email address will not be published. Required fields are marked *